Table 3: Harvested yields of cereals and potatoes and their concentrations of N, P, and K.

Crop

System

Nutrient concentrations (g 100 g DM−1)

Yield1 (kg ha−1)

N

P

K

Mean

s.e.2

c3

Mean

s.e.

c

Mean

s.e.

c

Mean

s.e.

c

CA1

5450

152

a

2.05

0.061

a

0.40

0.025

0.39

0.008

ab

CA2

5181

148

ab

1.99

0.054

ab

0.40

0.027

0.37

0.006

b

OA

2148

125

d

1.68

0.034

c

0.41

0.015

0.39

0.009

ab

Barley

CM

4865

134

b

1.85

0.034

bc

0.39

0.019

0.37

0.006

b

OM1

3881

130

c

1.77

0.035

bc

0.40

0.019

0.40

0.003

ab

OM2

4017

153

c

1.94

0.042

ab

0.42

0.020

0.41

0.006

a

LSD

347

0.18

n.s.

0.02

CA1

5866

260

a

2.07

0.050

0.38

0.020

0.37

0.006

Oats

CA2

5264

214

a

1.99

0.059

0.39

0.012

0.39

0.007

OA4

2618

297

b

2.30

0.155

0.43

0.012

0.59

0.012

LSD

944

n.s.

n.s.

n.s.

CA1

5696

217

a

2.25

0.047

0.40

0.023

0.40

0.002

CA2

5606

252

a

2.30

0.037

0.41

0.018

0.39

0.008

Wheat

OA

2494

185

d

2.23

0.070

0.45

0.012

0.39

0.007

CM

4900

260

b

2.34

0.044

0.42

0.014

0.39

0.005

OM1

3719

187

c

2.21

0.078

0.42

0.013

0.39

0.009

LSD

574

n.s.

n.s.

n.s.

CA1

9474

328

1.20

0.016

0.30

0.004

1.45

0.047

Potatoes

CA2

9535

349

1.22

0.038

0.28

0.001

1.42

0.058

LSD

n.s.

n.s.

n.s.

n.s.

1Yields of cereals were corrected to a water content of 15%, whereas yields of potatoes are presented as DM.
2Standard error of means. Yield data were averaged for the years 2001–2010, whereas data on nutrient concentrations were averaged for the years 2006–2010.
3Pairwise comparisons of yields/nutrient concentrations using LSD at the 5% level, where yields/nutrient concentration of the same crop differing significantly between systems are denoted different letters. Nonsignificant comparisons are denoted n.s.
4In the organic system OA, oat was grown in a mixture with peas. Yields are given as the sum of the two crops, whereas nutrient concentrations are given as a weighted average (based on the DM weights of the two crops).